1. Field
This disclosure relates generally to semiconductor processing, and more specifically, to a semiconductor wafer plating bus.
2. Related Art
In semiconductor processing, plating may be used for forming wirebond pads, in which a metal layer is plated over the last metal layer to form the bond pad. Plating may be performed using either an electroless plating process or an electrolytic plating process. In order to plate features on a semiconductor wafer using an electrolytic plating process, a plating bus layer is first applied over the final passivation layer and subsequently removed after the features are plated. However, the processes of applying and removing the plating bus are added cost processes. Electroless plating is a less expensive process, as compared to electrolytic plating, in which, rather than forming a plating bus, metal surfaces exposed by the final passivation layer are activated for the plating. However, electroless plating is harder to control than electrolytic plating and therefore results in reduced yield.